In Wednesday’s New York Times, I wrote about two experimental projects in California to store solar energy produced by photovoltaic rooftop arrays:

In the garage of Peter Rive’s San Francisco home is a battery pack. It is not connected to Mr. Rive’s electric Tesla Roadster sports car, but to the power grid.

The California Public Utilities Commission has awarded $1.8 million to Mr. Rive’s company, SolarCity, a residential photovoltaic panel installer, to research the feasibility of storing electricity generated by rooftop solar arrays in batteries.

As rooftop solar systems provide a growing percentage of electricity to California’s grid, regulators and utilities are increasingly concerned about how to balance the intermittent nature of that power with demand.

One possible solution is to store energy generated by solar arrays in batteries and other systems and then feed that electricity to the grid when, say, a cloudy day results in a drop in power production. And when demand peaks, electricity generated from renewable sources could be dispatched from batteries rather than fossil-fuel burning power plants.

“As soon as distributed solar starts providing 5 to 10 percent of demand, its intermittent nature will need to be addressed,” said Mr. Rive, who is SolarCity’s co-founder and chief operating officer.

SolarCity is teaming with Tesla Motors, the Silicon Valley electric car company run by Mr. Rive’s cousin, Elon Musk, and the University of California, Berkeley, to study how to integrate solar arrays and off-the-shelf Tesla lithium-ion battery backs into the grid. SolarCity plans to put such systems in six homes.

“We think in the years ahead this will be the default way that solar is installed,” Mr. Rive said. “Getting the costs down, though, is not going to be an easy task.”

Homeowners could potentially benefit by tapping batteries at hours when electricity rates are high or using them to provide backup power if the grid goes down.

The research has just begun, and at the moment SolarCity is testing the impact of charging and discharging electricity from the Tesla battery pack in Mr. Rive’s garage. His roof sports a three-kilowatt solar array.

“We’re at the point now where we can direct the battery to charge and discharge at specific times by sending a signal over the Internet,” Mr. Rive said.

Included in the $14.6 million awarded for solar energy storage research by the utilities commission was $1.9 million to SunPower for a project that will store in ice and batteries electricity generated by solar arrays at Target stores.

SunPower, a Silicon Valley solar panel manufacturer and power plant developer, will work with Ice Energy, a Colorado company that makes systems that use electricity when rates are low to form ice. When rates are high, air conditioning refrigerant is cooled by the melting ice rather than by an electricity-hogging compressor.

The Ice Bear system and a solar array will be installed at one Target store while battery packs will be used at two other stores in California.

photo: Todd Woody

In Wednesday’s New York Times, I write about a growing movement to repurpose farmland and toxic waste sites for big renewable energy projects:

LEMOORE, Calif. — Thousands of acres of farmland here in the San Joaquin Valley have been removed from agricultural production, largely because the once fertile land is contaminated by salt buildup from years of irrigation.

But large swaths of those dry fields could have a valuable new use in their future — making electricity.

Farmers and officials at Westlands Water District, a public agency that supplies water to farms in the valley, have agreed to provide land for what would be one of the world’s largest solar energy complexes, to be built on 30,000 acres.

At peak output, the proposed Westlands Solar Park would generate as much electricity as several big nuclear power plants.

Unlike some renewable energy projects blocked by objections that they would despoil the landscape, this one has the support of environmentalists.

The San Joaquin initiative is in the vanguard of a new approach to locating renewable energy projects: putting them on polluted or previously used land. The Westlands project has won the backing of groups that have opposed building big solar projects in the Mojave Desert and have fought Westlands for decades over the district’s water use. Landowners and regulators are on board, too.

“It’s about as perfect a place as you’re going to find in the state of California for a solar project like this,” said Carl Zichella, who until late July was the Sierra Club’s Western renewable programs director. “There’s virtually zero wildlife impact here because the land has been farmed continuously for such a long time and you have proximity to transmission, infrastructure and markets.”

Recycling contaminated or otherwise disturbed land into green energy projects could help avoid disputes when developers seek to build sprawling arrays of solar collectors and wind turbines in pristine areas, where they can affect wildlife and water supplies.

The United States Environmental Protection Agency and the National Renewable Energy Laboratory, for instance, are evaluating a dozen landfills and toxic waste sites for wind farms or solar power plants. In Arizona, the Bureau of Land Management has begun a program to repurpose landfills and abandoned mines for renewable energy.

In Southern California, the Los Angeles Department of Water and Power has proposed building a 5,000-megawatt solar array complex, part of which would cover portions of the dry bed of Owens Lake, which was drained when the city began diverting water from the Owens Valley in 1913. Having already spent more than $500 million to control the intense dust storms that sweep off the lake, the agency hopes solar panels can hold down the dust while generating clean electricity for the utility. A small pilot project will help determine if solar panels can withstand high winds and dust.

“Nothing about this is simple, but it’s worth doing,” Austin Beutner, the department’s interim general manager, said of the pilot program.

All of the projects are in early stages of development, and many obstacles remain. But the support they’ve garnered from landowners, regulators and environmentalists has attracted the interest of big solar developers such as SunPower and First Solar as well as utilities under pressure to meet aggressive renewable energy mandates.

Those targets have become harder to reach as the sunniest undeveloped land is put off limits.

Last December, Senator Dianne Feinstein, Democrat of California, introduced legislation to protect nearly a million acres of the Mojave Desert from renewable energy development.

But the senator’s bill also includes tax incentives for developers who build renewable energy projects on disturbed lands.

For Westlands farmers, the promise of the solar project is not clean electricity, but the additional water allocations they will get if some land is no longer used for farming.

“Westlands’ water supply has been chronically short over the past 18 years, so one of the things we’ve tried to do to balance supply and demand is to take land out of production,” said Thomas W. Birmingham, general manager of the water district, which acquired 100,000 acres and removed the land from most agricultural production. “The conversion of district-owned lands into areas that can generate electricity will help to reduce the cost of providing water to our farmers.”

photo: Ausra

The week kicked off with French nuclear energy giant Areva’s acquisition of Silicon Valley solar company Ausra. As I wrote Monday in the Los Angeles Times:

French nuclear energy giant Areva has jumped into the U.S. renewable energy market with the acquisition of Ausra, a Silicon Valley solar power plant startup backed by high-profile venture capitalists.
Terms of the deal were not disclosed, but in an interview on Monday, Areva executive Anil Srivastava said that the price the company paid for Ausra was in line with the $418 million that rival Siemens spent last year to acquire Solel, an Israel solar power plant builder.

That would be a decent payday for Ausra’s investors, which include marquee Silicon Valley venture capital firms Kleiner Perkins Caufield & Byers and Khosla Ventures.

“The current shareholders are very well-reputed venture capitalists and I can assure you they negotiated very well,” said Srivastava, the chief executive of Areva’s renewable energy division.

And the week is ending with Thursday’s announcement of another Silicon Valley-European deal. This time, as I write in The New York Times, California’s SunPower is acquiring a European solar developer:

SunPower, a leading Silicon Valley solar company, said on Thursday that it has agreed to acquire SunRay Renewable Energy, a European photovoltaic power plant builder, in a $277 million deal.

The acquisition follows Monday’s purchase of Ausra, another Silicon Valley solar technology company, by Areva, the French nuclear energy giant in a deal that an Areva executive valued at around $400 million.

SunPower has previously supplied solar panels to SunRay, which has a pipeline of projects in Europe and Israel that totals 1,200 megawatts. SunRay, which is headquartered in Malta, is owned by its management and Denham Capital.

photo: Southern California Edison

It hasn’t received much media attention, but the California Public Utilities Commission has just proposed instituting a first-of-its-kind reverse auction market to spur renewable energy development — mainly solar photovoltaic. As I write today in The New York Times:

California regulators are taking an eBay approach to ramping-up renewable energy in the Golden State.

In what might be a world first, the California Public Utilities Commission on Thursday proposed letting developers bid on contracts to install green energy projects. A solar company that offers to sell electricity to one of California’s three big utilities at a rate lower than its competitors would win a particular power purchase agreement.

This “reverse auction market” feed-in tariff is designed to avoid the pitfalls the have plagued efforts in Europe to encourage development of renewable energy by paying artificially high rates for electricity produced by solar power plants or rooftop photovoltaic projects.

photos: Schott

German solar company Schott on Monday cut the ribbon on a $100 million factory in Albuquerque, N.M., that will produce solar panels as well as receivers for solar trough power plants. Meanwhile, Chinese solar giant Suntech said Monday that it will build a solar cell manufacturing plant in the United States.

The move to North America comes as the European market softens as government subsidies ebb and solar panel prices fall. Despite the severe U.S. recession, Schott and Suntech are betting that the solar market will boom when the economy recovers and they’ll gain a competitive edge by manufacturing near customers.

“We think North America in general is the next big market for solar power,” Gerald Fine, CEO of Schott Solar’s North American operations, told Green Wombat. “Especially in the case of concentrated solar receivers you want to be close to your customers and provide great customer service and low shipping costs.”

And it doesn’t hurt to be generating green jobs as well. The 200,000-square-foot New Mexico factory employs 350 people. The plant was built too late to take advantage of the Obama stimulus package’s 30% tax credit for renewable energy manufacturing. But Fine said the tax credit will encourage Schott’s plans to eventually expand the facility to 800,000 square feet with a workforce of 1,500.

The receivers the factory makes are long glass-covered steel tubes that sit above parabolic troughs in large solar farms. The troughs concentrate sunlight on the receivers to heat a synthetic oil inside that is used to create steam that drives an electricity-generating turbine.

Fine declined to discuss specific customers for the receivers but there are numerous solar trough power plants being planned for the Southwest, including Abengoa Solar’s Solana project in Arizona and utility FPL’s (FPL) Beacon 250-megawatt solar in California.

“We feel pretty comfortable with our order books in both product lines for the foreseeable future,” said Fine. “If you look at the publicly announced plans and try to put a reasonable probability of them being completed, there’s in excess of two gigawatts of power plants out there.”

Schott will have the North American receiver market to itself but will face some stiff competition when it comes to making photovoltaic modules. Thin-film solar cell maker First Solar (FSLR) is headquartered in neighboring Arizona and claims the lowest cost of manufacturing. Last year, German solar cell maker SolarWorld opened a factory outside Portland, Ore., while Silicon Valley’s SunPower (SPWRA) makes some of the most efficient solar cells — albeit overseas.

And now China’s Suntech (STP) is moving into the U.S. manufacturing market. The company on Monday said it is looking at several states as potential sites for a factory and will make a decision on where to locate the facility within six months

“We believe in the outstanding long-term prospects of the solar energy market in the United States, and we will continue to invest in our ability to meet a substantial portion of that potential growth through in-market manufacturing,” Suntech CEO Zhengrong Shi said in a statement.

photo: BrightSource Energy

As the Nevada legislature debates extending tax breaks for large-scale solar power plants, a new report finds that ramping up solar development in the Silver State could produce thousands of good-paying green jobs while generating nearly $11 billion in economic benefits.

The study from San Francisco-based non-profit Vote Solar concludes that 2,000 megawatts’ worth of big solar thermal and photovoltaic farms — needed to meet Nevada’s electricity demand — would result in 5,900 construction jobs a year during the plants’ building phase, 1,200 permanent jobs and half a billion dollars in tax revenues.

“It is likely that such an investment in solar generating facilities could bring solar and related manufacturing to Nevada,” the reports authors wrote. “The economic impact of such manufacturing development is not included in this analysis, but would add significant additional benefits.”

Vote Solar’s job projections are based on an economic model developed by the National Renewable Energy Laboratory to project the impact of solar trough power plants, the most common, if dated, type of Big Solar technology.

The different solar technologies set to come online in the next couple of years could change that equation. No doubt thousands of jobs will be generated by Big Solar but just how many will depend on the mix of solar thermal and photovoltaic power plants that ultimately come online. New technologies like BrightSource Energy’s “power tower,”Ausra’s compact linear fresnel reflector and Stirling Energy Systems’s solar dish may generate similar numbers of jobs. But then there’s eSolar’s power tower solar farms – which uses fields of mirrors called heliostats to focus the sun on a water-filled boiler, creating steam that drives an electricity-generating turbine. eSolar’s small and prefabricated heliostat arrays cut out much of the skilled labor typically needed on such projects as they can be installed by two workers using a wrench.

Photovoltaic farms essentially take rooftop solar panels and put them on the ground and thus don’t require highly skilled laborers to build turbine power blocks, miles of piping and other infrastructure needed in solar thermal facilities. (They also can be built much more quickly than a solar thermal plant, which is why utilities have been striking deals with companies like First Solar (FSLR) and SunPower (SPWRA) for PV farms.)

A second report released this week — from the Large-Scale Solar Association, an industry group — found that Nevada could gain an edge over Arizona and California in luring solar power plant builders if it extended and sweetened tax incentives. The three states form something of a golden triangle of solar, offering the nation’s most intense sunshine and vast tracts of government-owned desert land that are being opened up for solar development.

The timing of the reports was no accident. The Nevada Legislature held hearings earlier this week on extending tax breaks for Big Solar that expire in June, and Vote Solar’s utility-scale solar policy director, Jim Baak, went to Carson City to lobby legislators, hoping to head off one proposal to tax renewable energy production.

The Large-Scale Solar report, prepared by a Las Vegas economic consulting firm, found that if legislators let the tax breaks sunset, as it were, the developer of a 100-megawatt solar power plant would pay $55.1 million in taxes in Nevada during the first 15 years of the facility’s operation compared to $26.1 million in Arizona and between $36.1 and $37.9 million in California. If the current incentives are kept, tax payments drop to $25.1 million. A bigger tax break would reduce the tax burden to $14.3 million.

photo: WorldWater & Solar Technologies

The consolidation of the solar industry got underway Monday with the acquisition of San Francisco-based green energy financier MMA Renewable Ventures by Spanish solar developer Fotowatio.

The Madrid-based company will purchase most of MMA Renewable’s solar assets – including the world largest photovoltaic power plant and its pipeline of projects – making it one of the biggest solar developers in the United States.

The financial terms of the deal were not disclosed.

MMA Renewable CEO Matt Cheney told Green Wombat that he’ll continue as CEO of what will be called, for now, Renewable Ventures and that his staff will be joining him. MMA Renewable Ventures was a subsidiary of Municipal Mortgage & Equity, which has been hit hard by the financial crisis.

Fotowatio, on the other hand, scored $350 million in funding last July from General Electric (GE) and Grupo Corporativo Landon. “You’re taking a very robust player in the European market see how much opportunity and potential there is in the U.S. market,” says Cheney. “It’ll produce one of the biggest, if not the biggest, independent solar power producers. It’s the story of consolidation.”

When the deal closes, Fotowatio will gain 35 megawatts of solar projects in the U.S. with another 400 megawatts under development.

Cheney says the Fotowatio acquisition is a sign of the times as the global economic crisis and falling prices for solar cells disrupts the renewable energy market. “There’s a shakeout in the marketplace and there’s opportunities for consolidation.”

About Green Wombat

Green Wombat is written by
Todd Woody, a veteran environmental journalist based in California who writes for The New York Times, the Los Angeles Times, Grist and Yale e360. He's one of the few people on the planet who have held a northern hairy-nosed wombat in the wild.

Todd formerly was a senior editor at Fortune magazine, an assistant managing editor at Business 2.0 magazine and the business editor of the San Jose Mercury News.